1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/07 04:10:30
1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
=5/4-9/20+11/30-13/42+15/56-17/72+19/90
=5/4-(4+5)/4*5+(5+6)/5*6-(6+7)/6*7+(7+8)/7*8-(8+9)/8*9+(9+10)/9*10
=5/4-1/4-1/5+1/5+1/6-1/6-1/7+1/7+1/8-1/8-1/9+1/9+1/10
=1+1/10
=11/10.

=1+1/2-(2+3)/(2*3)+(3+4)/(3*4).....+(9+10)/(9*10)
=1+1/2-(1/3+1/2)+(1/4+1/3)-.....+(1/9+1/10(
=1+1/10
=11/10